Nail varnish composition comprising a sequenced polymer

ABSTRACT

The present invention relates to a nail varnish composition comprising, in a cosmetically acceptable medium, at least one particular block polymer, the said composition being free of nitrocellulose and having a mean gloss greater than 50 out of 100. A subject of the invention is also the use of such a composition to obtain a film, deposited on the nails, which is glossy and which shows good staying power and wear resistance.

The present invention relates to a nail varnish free from nitrocellulosecomprising a block polymer. The invention also relates to a makeup orcare process for the nails. These compositions may be applied to humannails or to false nails.

The compositions to be applied to the nails, of the type such assolvent-based nail varnishes or nailcare bases, usually comprise atleast one film-forming polymer, optionally plasticizer, pigments,rheological agents and solvents.

Nitrocellulose is a film-forming agent commonly used in solvent-basednail varnishes to obtain glossy compositions with good strength.

Nitrocellulose is a polymer consisting of an assembly of partiallynitrated anhydroglucose rings obtained by esterification of some of thefree hydroxyl functions of a cellulose with nitric acid in the presenceof sulfuric acid.

At the present time, nitrocellulose is still the main film-forming agentthe most widely used in solvent-based nail varnishes in formulationswith optimized gloss and strength.

However, formulations comprising nitrocelluloses have the followingdrawbacks:

-   -   they make it possible to obtain films with satisfactory levels        of hardness and gloss, but with unsatisfactory strength over        time, especially due to the poor chip strength of the film;    -   they give hard films that lack adhesion to the nail.        This drawback may be overcome by adding plasticizers, but, in        this case, very large amounts of plasticizers and of co-resins,        of the order of that of nitrocellulose, need to be used.        Furthermore, the presence of plasticizers in these formulations        is reflected, after film formation and drying, especially by a        change in the properties of the film over time, due both to slow        evaporation of the residual solvents contained in the film after        drying, and to a potential loss of some of the plasticizers,        especially by evaporation, resulting in hardening of the film        over time and poor chip strength.

Certain known formulations comprising nitrocellulose have the drawbackof yellowing on the nail over time. In addition, the manufacture ofnitrocellulose, its transportation and its incorporation intoformulations pose safety problems which are such that it is sought toreplace it with other film-forming agents.

The studies conducted with regard to the replacement of nitrocellulosewith other film-forming agents such as polyacrylics and polyurethanes innail varnishes, for instance the aqueous polyurethane dispersionsdescribed in document EP 0 648 485, have not given satisfactory results,especially in terms of strength and resistance to external factors suchas water or detergents.

Patent application US 2002/18759 describes an acrylic acid/butylmethacrylate copolymer as film-forming polymer for partially replacingnitrocellulose. Nail varnishes containing this polymer do not showsufficient strength and in particular sufficient gloss strength, andrequire the addition of plasticizers.

The Applicant has discovered a novel route for formulating anitrocellulose-free nail varnish that has good gloss and strengthproperties.

This nail varnish also makes it possible to obtain plasticization offilms without the need to add large amounts of external plasticizers,while at the same time maintaining a good level of hardness of the filmsand good impact strength and/or chip strength of the varnishes on thenail, and thus an improvement in the strength over time of the varnisheson the nail and/or in their wear resistance.

One subject of the invention is, more specifically, a nail varnishcomposition comprising, in a cosmetically acceptable organic solvent, atleast one linear ethylenic film-forming block polymer, the saidcomposition being free of nitrocellulose, the block polymer being suchthat, when it is present in sufficient amount in the composition, themean gloss at 20° of a deposit of the said composition, once spread ontoa support, is greater than or equal to 50 out of 100.

A subject of the invention is also a nail varnish compositioncomprising, in a cosmetically acceptable medium, at least one linearblock ethylenic film-forming polymer as described below, the saidcomposition being free of nitrocellulose.

The term “nitrocellulose” means any nitrated cellulose derivative, inparticular nitrocellulose.

According to the present invention, the term “film-forming polymer”means a polymer that is capable of forming, by itself or in the presenceof an auxiliary film-forming agent, a continuous film that adheres to asupport, and especially to keratin materials.

The term “nitrocellulose-free composition” means a compositioncontaining less than 5%, preferably less than 3%, preferably less than2%, preferably less than 1%, preferably less than 0.5%, preferably lessthan 0.1% and preferably less than 0.05% of nitrocellulose.

A subject of the invention is also a non-therapeutic cosmetic processfor making up or caring for the nails, comprising the application to thenails of at least one coat of the nail varnish composition as definedabove.

A subject of the invention is also a nail varnish composition comprisingat least one film-forming linear ethylenic block polymer, the saidcomposition being free of nitrocellulose, to obtain a film, once spreadonto a support, which has a gloss at 200 of greater than 50 out of 100,and which incidentally has good strength.

Mean Gloss of the Composition

The term “mean gloss” means the gloss as may be conventionally measuredusing a glossmeter by the following method.

A coat of between 50 μm and 150 μm in thickness of the composition isspread using an automatic spreader onto a Leneta brand contrast card ofreference Form 1A Penopac. The coat covers at least the white backgroundof the card. The deposit is left to dry for 24 hours at a temperature of30° C., and the gloss at 20° is then measured on the white backgroundusing a Byk Gardner brand glossmeter of reference microTri-Gloss.

This measurement (between 0 and 100) is repeated at least three times,and the mean gloss is the mean of the at least three measurements taken.

The mean gloss of the composition measured at 20° is advantageouslygreater than or equal to 50 out of 100, better still greater than orequal to 55, even better still greater than or equal to 60, even betterstill greater than or equal to 65, even better still greater than orequal to 70 or even better still greater than or equal to 75 out of 100,or even greater than or equal to 80 out of 100.

Preferably, the mean gloss of the composition, once spread onto asupport, measured at 60° is greater than or equal to 50, better stillgreater than or equal to 60, better still greater than or equal to 65,better still greater than or equal to 70, better still greater than orequal to 75, better still greater than or equal to 80, better stillgreater than or equal to 85 or better still greater than or equal to 90out of 100.

The mean gloss at 60° is measured as follows. The gloss may beconventially measured using a glossmeter by the following method.

A coat of between 50 μm and 150 μm in thickness of the composition isspread using an automatic spreader onto a Leneta brand contrast card ofreference Form 1A Penopac. The coat covers at least the white backgroundof the card. The deposit is left to dry for 24 hours at a temperature of30° C., and the gloss at 60° is then measured on the white backgroundusing a Byk Gardner brand glossmeter of reference microTri-Gloss.

This measurement (between 0 and 100) is repeated at least three times,and the mean gloss is the mean of the at least three measurements taken.

According to one embodiment, the gloss of the composition measured at20° is preferably greater than or equal to 60, preferably 65, 70 or 75out of 100, and/or the gloss of the composition measured at 60° ispreferably greater than or equal to 80, 85 or 90 out of 100.

Block Polymer:

The composition according to the present invention contains at least oneblock polymer. The term “block polymer” means a polymer comprising atleast two different blocks and preferably at least three differentblocks.

According to one embodiment, the block polymer of the compositionaccording to the invention is an ethylenic polymer. The term “ethylenicpolymer” means a polymer obtained by polymerization of ethylenicallyunsaturated monomers.

According to one embodiment, the block polymer of the compositionaccording to the invention is a linear polymer. In contrast, a polymerof non-linear structure is, for example, a polymer of branched,starburst or grafted structure, or the like.

According to one embodiment, the block polymer of the compositionaccording to the invention is a film-forming polymer. The term“film-forming polymer” means a polymer that is capable of forming, byitself or in the presence of an auxiliary film-forming agent, acontinuous film that adheres to a support and especially to keratinmaterials.

According to one embodiment, the block polymer of the compositionaccording to the invention is a non-elastomeric polymer.

The term “non-elastomeric polymer” means a polymer which, when subjectedto a stress intended to stretch it (for example by 30% relative to itsinitial length), does not return to a length substantially identical toits initial length when the stress is removed.

More specifically, the expression “non-elastomeric polymer” means apolymer with an instantaneous recovery R_(i)<50% and a delayed recoveryR_(2h)<70% after having undergone a 30% elongation. Preferably, R_(i) is<30%, and R_(2h)<50%.

More specifically, the non-elastomeric nature of the polymer isdetermined according to the following protocol:

A polymer film is prepared by pouring a solution of the polymer into aTeflon-coated mould followed by drying for 7 days under ambientconditions regulated to 23±5° C. and 50±10% relative humidity.

A film about 100 μm thick is thus obtained, from which are cutrectangular specimens (for example using a punch) 15 mm wide and 80 mmlong.

This sample is subjected to a tensile stress using a machine sold underthe reference Zwick, under the same temperature and humidity conditionsas for the drying operation.

The specimens are drawn at a speed of 50 mm/minute and the distancebetween the jaws is 50 mm, which corresponds to the initial length (l₀)of the specimen.

The instantaneous recovery R_(i) is determined in the following manner:

-   -   the specimen is stretched by 30% (ε_(max)), i.e. about 0.3 times        its initial length (l₀)    -   the stress is released by applying a return speed equal to the        tensile speed, i.e. 50 mm/minute, and the residual percentage        elongation of the specimen, after returning to zero load        (ε_(i)), is measured.

The percentage instantaneous recovery (R_(i)) is given by the formulabelow:R _(i)=((ε_(max)−ε_(i))/ε_(max))×100

To determine the delayed recovery, the residual elongation of the sampleis measured as a percentage (ε_(2h)), 2 hours after returning to zerostress.

The percentage delayed recovery (R_(2h)) is given by the formula below:R _(2h)=((ε_(max)−ε_(2h))/ε_(max))×100

Purely by way of indication, a polymer according to an embodiment of theinvention has an instantaneous recovery R_(i) of 10% and a delayedrecovery R_(2h) of 30%.

According to another embodiment, the block polymer of the compositionaccording to the invention does not comprise any styrene units. Theexpression “polymer free of styrene units” means a polymer comprisingless than 10%, preferably less than 5%, preferentially less than 2% andmore preferentially less than 1% by weight i) of styrene units offormula —CH(C₆H₅)—CH₂— or ii) of substituted styrene units, for instancemethylstyrene, chlorostyrene or chloromethylstyrene.

According to one embodiment, the block polymer of the compositionaccording to the invention is derived from aliphatic ethylenic monomers.The term “aliphatic monomer” means a monomer comprising no aromaticgroups.

According to one embodiment, the block polymer is an ethylenic polymerderived from aliphatic ethylenic monomers comprising a carbon-carbondouble bond and at least one ester group —COO— or amide group —CON—. Theester group may be linked to one of the two unsaturated carbons via thecarbon atom or the oxygen atom. The amide group may be linked to one ofthe two unsaturated carbons via the carbon atom or the nitrogen atom.

According to one embodiment, the block polymer comprises at least onefirst block and at least one second block.

The term “at least one block” means one or more blocks.

It is pointed out that, in the text hereinabove and hereinbelow, theterms “first” and “second” blocks do not in any way condition the orderof the said blocks in the polymer structure.

According to one embodiment, the block polymer comprises at least onefirst block and at least one second block that have different glasstransition temperatures (Tg).

In this embodiment, the first and second blocks may be linked togethervia an intermediate segment with a glass transition temperature betweenthe glass transition temperatures of the first and second blocks.

According to one embodiment, the block polymer comprises at least onefirst block and at least one second block linked together via anintermediate segment comprising at least one constituent monomer of thefirst block and at least one constituent monomer of the second block.

Preferably, the intermediate block is derived essentially fromconstituent monomers of the first block and of the second block.

The term “essentially” means at least 85%, preferably at least 90%,better still 95% and even better still 100%.

Advantageously, the intermediate segment comprising at least oneconstituent monomer of the first block and at least one constituentmonomer of the second block of the polymer is a random polymer.

According to one embodiment, the block polymer comprises at least onefirst block and at least one second block that are incompatible in theorganic liquid medium of the composition of the invention.

The term “mutually incompatible blocks” means that the mixture formedfrom the polymer corresponding to the first block and from the polymercorresponding to the second block is not miscible in the organic liquidthat is in major amount by weight contained in the organic liquid mediumof the composition, at room temperature (25° C.) and atmosphericpressure (10⁵ Pa), for a content of the polymer mixture of greater thanor equal to 5% by weight, relative to the total weight of the mixture(polymers and major organic liquid), it being understood that:

i) the said polymers are present in the mixture in a content such thatthe respective weight ratio ranges from 10/90 to 90/10, and

ii) each of the polymers corresponding to the first and second blockshas an average (weight-average or number-average) molecular mass equalto that of the block polymer ±15%.

When the organic liquid medium comprises a mixture of organic liquids,in the case of two or more liquids present in identical massproportions, the said polymer mixture is immiscible in at least one ofthem.

When the organic liquid medium comprises only one organic liquid, thisliquid obviously constitutes the liquid that is in major amount byweight.

The term “organic liquid medium” means a medium containing at least oneorganic liquid, i.e. at least one organic compound that is liquid atroom temperature (25° C.) and atmospheric pressure (10⁵ Pa) According toone embodiment, the major liquid of the organic liquid medium is avolatile or non-volatile oil (fatty substance). Preferably, the organicliquid is cosmetically acceptable (acceptable tolerance, toxicology andfeel). The organic liquid medium is cosmetically acceptable, in thesense that it is compatible with keratin materials, for instance theoils or organic solvents commonly used in cosmetic compositions.

According to one embodiment, the major liquid of the organic liquidmedium is the polymerization solvent or one of the polymerizationsolvents of the block polymer, as are described below.

The term “polymerization solvent” means a solvent or a mixture ofsolvents. The polymerization solvent may be chosen especially from ethylacetate, butyl acetate, alcohols such as isopropanol and ethanol,aliphatic alkanes such as isododecane, and mixtures thereof. Preferably,the polymerization solvent is a mixture of butyl acetate andisopropanol, or isododecane.

In general, the block polymer may be incorporated into the compositionto a high solids content, typically greater than 10%, greater than 20%,more preferably greater than 30% and more preferentially greater than45% by weight relative to the total weight of the composition, while atthe same time being easy to formulate.

Preferably, the block polymer comprises no silicon atoms in itsskeleton. The term “skeleton” means the main chain of the polymer, asopposed to the pendent side chains.

Preferably, the polymer according to the invention is not water-soluble,i.e. the polymer is not soluble in water or in a mixture of water andlinear or branched lower monoalcohols containing from 2 to 5 carbonatoms, for instance ethanol, isopropanol or n-propanol, without pHmodification, at an active material content of at least 1% by weight, atroom temperature (25° C.).

According to one embodiment, the block polymer has a polydispersityindex I of greater than 2.

Advantageously, the block polymer used in the. compoisitions accordingto the invention has a polydispersity index greater than 2, for exampleranging from 2 to 9, preferably greater than or equal to 2.5, forexample ranging from 2.5 to 8 and better still greater than or equal to2.8 and especially ranging from 2.8 to 6.

The polydispersity index I of the polymer is equal to the ratio of theweight-average mass Mw to the number-average mass Mn.

The weight-average molar mass (Mw) and number-average molar mass (Mn)are determined by gel permeation liquid chromatography (THF solvent,calibration curve established with linear polystyrene standards,refractometric detector).

The weight-average mass (Mw) of the block polymer is preferably lessthan or equal to 300 000; it ranges, for example, from 35 000 to 200 000and better still from 45 000 to 150 000.

The number-average mass (Mn) of the block polymer is preferably lessthan or equal to 70 000; it ranges, for example, from 10 000 to 60 000and better still from 12 000 to 50 000.

Each block of the block polymer is derived from one type of monomer orfrom several different types of monomer.

This means that each block may consist of a homopolymer or a copolymer;this copolymer constituting the block may in turn be random oralternating.

The glass transition temperatures indicated for the first and secondblocks may be theoretical Tg values determined from the theoretical Tgvalues of the constituent monomers of each of the blocks, which may befound in a reference manual such as the Polymer Handbook, 3rd Edition,1989, John Wiley, according to the following relationship, known asFox's law:${{1/{Tg}} = {\sum\limits_{i}\left( {\varpi_{i}/{Tg}_{i}} \right)}},${overscore (ω)} being the mass fraction of the monomer i in the blockunder consideration and Tg_(i) being the glass transition temperature ofthe homopolymer of the monomer i.

Unless otherwise indicated, the Tg values indicated for the first andsecond blocks in the present patent application are theoretical Tgvalues.

The difference between the glass transition temperatures of the firstand second blocks is generally greater than 10° C., preferably greaterthan 20° C. and better still greater than 30° C.

In particular, the block polymer comprises at least one first block andat least one second block such that the first block may be chosen from:

a) a block with a Tg of greater than or equal to 40° C.,

b) a block with a Tg of less than or equal to 20° C.,

c) a block with a Tg of between 20 and 40° C., and the second block maybe chosen from a category a), b) or c) that is different from the firstblock.

In the present invention, the expression: “between . . . and . . . ” isintended to denote a range of values for which the limits mentioned areexcluded, and “from . . . to . . . ” and “ranging from . . . to . . . ”are intended to denote a range of values for which the limits areincluded.

a) Block With a Tg of Greater Than or Equal to 40° C.

The block with a Tg of greater than or equal to 40° C. has, for example,a Tg ranging from 40 to 150° C., preferably greater than or equal to 50°C., for example ranging from 50° C. to 120° C. and better still greaterthan or equal to 60° C., for example ranging from 60° C. to 120° C.

The block with a Tg of greater than or equal to 40° C. may be ahomopolymer or a copolymer.

The block with a Tg of greater than or equal to 40° C. may be totally orpartially derived from one or more monomers which are such that thehomopolymer prepared from these monomers has a glass transitiontemperature of greater than or equal to 40° C.

In the case where this block is a homopolymer, it is derived frommonomers which are such that the homopolymers prepared from thesemonomers have glass transition temperatures of greater than or equal to40° C. This first block may be a homopolymer consisting of only one typeof monomer (for which the Tg of the corresponding homopolymer is greaterthan or equal to 40° C.).

In the case where the first block is a copolymer, it may be totally orpartially derived from one or more monomers, the nature andconcentration of which are chosen such that the Tg of the resultingcopolymer is greater than or equal to 40° C. The copolymer may comprise,for example:

-   -   monomers which are such that the homopolymers prepared from        these monomers have Tg values of greater than or equal to 40°        C., for example a Tg ranging from 40 to 150° C., preferably        greater than or equal to 50° C., for example ranging from 50° C.        to 120° C. and better still greater than or equal to 60° C., for        example ranging from 60° C. to 120° C., and    -   monomers which are such that the homopolymers prepared from        these monomers have Tg values of less than 40° C., chosen from        monomers with a Tg of between 20 and 40° C. and/or monomers with        a Tg of less than or equal to 20° C., for example a Tg ranging        from −100 to 20° C., preferably less than 15° C., especially        ranging from −80° C. to 15° C. and better still less than 10°        C., for example ranging from −50° C. to 0° C., as described        later.

The monomers whose homopolymers have a glass transition temperature ofgreater than or equal to 40° C. are chosen, for example, from thefollowing monomers, also known as the main monomers:

-   -   methacrylates of formula CH₂═C(CH₃)—COOR₁ in which R₁ represents        a linear or branched unsubstituted alkyl group containing from 1        to 4 carbon atoms, such as a methyl, ethyl, propyl or isobutyl        group or R₁ represents a C₄ to C₁₂ cycloalkyl group,    -   acrylates of formula CH₂═CH—COOR₂ in which R₂ represents a C₄ to        C₁₂ cycloalkyl group such as isobornyl acrylate or a tert-butyl        group,    -   (meth)acrylamides of formula:        in which R₇ and R₈, which may be identical or different, each        represent a hydrogen atom or a linear or branched C₁ to C₁₂        alkyl group such as an n-butyl, t-butyl, isopropyl, isohexyl,        isooctyl or isononyl group; or R₇ represents H and R₈ represents        a 1,1-dimethyl-3-oxobutyl group, and R′ denotes H or methyl.        Examples of monomers that may be mentioned include        N-butylacrylamide, N-t-butylacrylamide, N-isopropylacrylamide,        N,N-dimethylacrylamide and N,N-dibutylacrylamide,    -   and mixtures thereof.

Main monomers that are particularly preferred are methyl methacrylate,isobutyl (meth)acrylate and isobornyl (meth)acrylate, and mixturesthereof.

b) Block with a Tg of Less Than or Equal to 20° C.

The block with a Tg of less than or equal to 20° C. has, for example, aTg ranging from −100 to 20° C., preferably less than or equal to 15° C.,especially ranging from −80° C. to 15° C. and better still less than orequal to 10° C., for example ranging from −50° C. to 0° C.

The block with a Tg of less than or equal to 20° C. may be a homopolymeror a copolymer.

The block with a Tg of less than or equal to 20° C. may be totally orpartially derived from one or more monomers which are such that thehomopolymer prepared from these monomers has a glass transitiontemperature of less than or equal to 20° C.

In the case where this block is a homopolymer, it is derived frommonomers which are such that the homopolymers prepared from thesemonomers have glass transition temperatures of less than or equal to 20°C. This second block may be a homopolymer consisting of only one type ofmonomer (for which the Tg of the corresponding homopolymer is less thanor equal to 20° C.).

In the case where the block with a Tg of less than or equal to 20° C. isa copolymer, it may be totally or partially derived from one or moremonomers, the nature and concentration of which are chosen such that theTg of the resulting copolymer is less than or equal to 20° C.

It may comprise, for example

-   -   one or more monomers whose corresponding homopolymer has a Tg of        less than or equal to 20° C., for example a Tg ranging from        −100° C. to 20° C., preferably less than 15° C., especially        ranging from −80° C. to 15° C. and better still less than 10°        C., for example ranging from −50° C. to 0° C., and    -   one or more monomers whose corresponding homopolymer has a Tg of        greater than 20° C., such as monomers with a Tg of greater than        or equal to 40° C., for example a Tg ranging from 40 to 150° C.,        preferably greater than or equal to 50° C., for example ranging        from 50° C. to 120° C. and better still greater than or equal to        60° C., for example ranging from 60° C. to 120° C. and/or        monomers with a Tg of between 20 and 40° C., as described above.

Preferably, the block with a Tg of less than or equal to 20° C. is ahomopolymer.

The monomers whose homopolymer has a Tg of less than or equal to 20° C.are preferably chosen from the following monomers, or main monomer:

-   -   acrylates of formula CH₂═CHCOOR₃,        R₃ representing a linear or branched C₁ to C₁₂ unsubstituted        alkyl group, with the exception of the tert-butyl group, in        which one or more hetero atoms chosen from O, N and S is (are)        optionally intercalated,    -   methacrylates of formula CH₂═C(CH₃)—COOR₄,        R₄ representing a linear or branched C₆ to C₁₂ unsubstituted        alkyl group, in which one or more hetero atoms chosen from O, N        and S is (are) optionally intercalated,    -   vinyl esters of formula R₅—CO—O—CH═CH₂        in which R₅ represents a linear or branched C₄ to C₁₂ alkyl        group,    -   C₄ to C₁₂ alkyl vinyl ethers,    -   N-(C₄ to C₁₂)alkyl acrylamides; such as N-octylacrylamide,    -   and mixtures thereof.

The main monomers that are particularly preferred for the block with aTg of less than or equal to 20° C. are alkyl acrylates whose alkyl chaincontains from 1 to 10 carbon atoms, with the exception of the tert-butylgroup, such as methyl acrylate, isobutyl acrylate and 2-ethylhexylacrylate, and mixtures thereof.

c) Block With a Tg of Between 20 and 40° C.

The block with a Tg of between 20 and 40° C. may be a homopolymer or acopolymer.

The block with a Tg of between 20 and 40° C. may be totally or partiallyderived from one or more monomers which are such that the homopolymerprepared from these monomers has a glass transition temperature ofbetween 20 and 40° C.

The block with a Tg of between 20 and 40° C. may be totally or partiallyderived from monomers which are such that the corresponding homopolymerhas a Tg of greater than or equal to 40° C., and from monomers which aresuch that the corresponding homopolymer has a Tg of less than or equalto 20° C.

In the case where this block is a homopolymer, it is derived frommonomers (or main monomer) which are such that the homopolymers preparedfrom these monomers have glass transition temperatures of between 20 and40° C. This first block may be a homopolymer, consisting of only onetype of monomer (for which the Tg of the corresponding homopolymerranges from 20° C. to 40° C.).

The monomers whose homopolymer has a glass transition temperature ofbetween 20 and 40° C. are preferably chosen from n-butyl methacrylate,cyclodecyl acrylate, neopentyl acrylate and isodecylacrylamide, andmixtures thereof.

In the case where the block with a Tg of between 20 and 40° C. is acopolymer, it is totally or partially derived from one or more monomers(or main monomer) whose nature and concentration are chosen such thatthe Tg of the resulting copolymer is between 20 and 40° C.

Advantageously, the block with a Tg of between 20 and 40° C. is acopolymer totally or partially derived from:

-   -   main monomers whose corresponding homopolymer has a Tg of        greater than or equal to 40° C., for example a Tg ranging from        40° C. to 150° C., preferably greater than or equal to 50° C.,        for example ranging from 50 to 120° C. and better still greater        than or equal to 60° C., for example ranging from 60° C. to 120°        C., as described above, and/or    -   main monomers whose corresponding homopolymer has a Tg of less        than or equal to 20° C., for example a Tg ranging from −100 to        20° C., preferably less than or equal to 15° C., especially        ranging from −80° C. to 15° C. and better still less than or        equal to 10° C., for example ranging from −50° C. to 0° C., as        described above, the said monomers being chosen such that the Tg        of the copolymer forming the first block is between 20 and 40°        C.

Such main monomers are chosen, for example, from methyl methacrylate,isobornyl acrylate and methacrylate, butyl acrylate and 2-ethylhexylacrylate, and mixtures thereof.

Preferably, the proportion of the second block with a Tg of less than orequal to 20° C. ranges from 10% to 85% by weight, better still from 20%to 70% and even better still from 20% to 50% by weight of the polymer.

Preferably, each of the first and second blocks comprises at least onemonomer chosen from acrylic acid, acrylic acid esters, (meth)acrylicacid and (meth)acrylic acid esters, and mixtures thereof.

Advantageously, each of the first and second blocks is totally derivedfrom at least one monomer chosen from acrylic acid, acrylic acid esters,(meth)acrylic acid and (meth)acrylic acid esters, and mixtures thereof.

However, each of the blocks may contain in small proportion at least oneconstituent monomer of the other block.

Thus, the first block may contain at least one constituent monomer ofthe second block, and vice versa.

Each of the first and/or second blocks may comprise, in addition to themonomers indicated above, one or more other monomers known as additionalmonomers, which are different from the main monomers mentioned above.

The nature and amount of this or these additional monomer(s) are chosensuch that the block in which they are present has the desired glasstransition temperature.

This additional monomer is chosen, for example, from:

hydrophilic monomers such as:

-   -   ethylenically unsaturated monomers comprising at least one        carboxylic or sulphonic acid function, for instance:

acrylic acid, methacrylic acid, crotonic acid, maleic anhydride,itaconic acid, fumaric acid, maleic acid, acrylamidopropanesulphonicacid, vinylbenzoic acid, vinylphosphoric acid, and salts thereof,

-   -   ethylenically unsaturated monomers comprising at least one        tertiary amine function, for instance 2-vinylpyridine,        4-vinylpyridine, dimethylaminoethyl methacrylate,        diethylaminoethyl methacrylate and        dimethylaminopropylmethacrylamide, and salts thereof,    -   methacrylates of formula CH₂═C(CH₃)—COOR₆

in which R₆ represents a linear or branched alkyl group containing from1 to 4 carbon atoms, such as a methyl, ethyl, propyl or isobutyl group,the said alkyl group being substituted with one or more substituentschosen from hydroxyl groups (for instance 2-hydroxypropyl methacrylateand 2-hydroxyethyl methacrylate) and halogen atoms (Cl, Br, I or F),such as trifluoroethyl methacrylate,

-   -   methacrylates of formula CH₂═C(CH₃)—COOR₉,

R₉ representing a linear or branched C₆ to C₁₂ alkyl group in which oneor more hetero atoms chosen from O, N and S is (are) optionallyintercalated, the said alkyl group being substituted with one or moresubstituents chosen from hydroxyl groups and halogen atoms (Cl, Br, I orF);

-   -   acrylates of formula CH₂═CHCOOR₁₀,

R₁₀ representing a linear or branched C₁ to C₁₂ alkyl group substitutedwith one or more substituents chosen from hydroxyl and halogen atoms(Cl, Br, I or F), such as 2-hydroxypropyl acrylate and 2-hydroxyethylacrylate, or R₁₀ represents a (C₁-C₁₂) alkyl-O-POE (polyoxyethylene)with repetition of the oxyethylene unit 5 to 30 times, for examplemethoxy-POE, or R₁₀ represents a polyoxyethylenated group comprisingfrom 5 to 30 ethylene oxide units

b) ethylenically unsaturated monomers comprising one or more siliconatoms, such as methacryloxypropyltrimethoxysilane andmethacryloxypropyltris(trimethylsiloxy)silane,

-   -   and mixtures thereof.

Additional monomers that are particularly preferred are acrylic acid,methacrylic acid and trifluoroethyl methacrylate, and mixtures thereof.

According to one embodiment, each of the first and second blocks of theblock polymer comprises at least one monomer chosen from (meth)acrylicacid esters and optionally at least one additional monomer such as(meth)acrylic acid, and mixtures thereof.

According to another embodiment, each of the first and second blocks ofthe block polymer is totally derived from at least one monomer chosenfrom (meth)acrylic acid esters and optionally from at least oneadditional monomer such as (meth)acrylic acid, and mixtures thereof.

According to one preferred embodiment, the block polymer is anon-silicone polymer, i.e. a polymer free of silicon atoms.

This or these additional monomer(s) generally represent(s) an amount ofless than or equal to 30% by weight, for example from 1% to 30% byweight, preferably from 5% to 20% by weight and more preferably from 7%to 15% by weight, relative to the total weight of the first and/orsecond blocks.

The block polymer may be obtained by free-radical solutionpolymerization according to the following preparation process:

-   -   a portion of the polymerization solvent is introduced into a        suitable reactor and heated until the adequate temperature for        the polymerization is reached (typically between 60 and 120°        C.),    -   once this temperature is reached, the constituent monomers of        the first block are introduced in the presence of some of the        polymerization initiator, after a time T corresponding to a        maximum degree of conversion of 90%, the constituent monomers of        the second block and the rest of the initiator are introduced,    -   the mixture is left to react for a time {dot over (T)}′ (ranging        from 3 to 6 hours), after which the mixture is cooled to room        temperature,        -   the polymer dissolved in the polymerization solvent is            obtained.

FIRST EMBODIMENT

According to a first embodiment, the block polymer comprises a firstblock with a Tg of greater than or equal to 40° C., as described abovein a) and a second block with a Tg of less than or equal to 20° C., asdescribed above in b).

Preferably, the first block with a Tg of greater than or equal to 40° C.is a copolymer derived from monomers which are such that the homopolymerprepared from these monomers has a glass transition temperature ofgreater than or equal to 40° C., such as the monomers described above.

Advantageously, the second block with a Tg of less than or equal to 20°C. is a homopolymer derived from monomers which are such that thehomopolymer prepared from these monomers has a glass transitiontemperature of less than or equal to 20° C., such as the monomersdescribed above.

Preferably, the proportion of the block with a Tg of greater than orequal to 40° C. ranges from 20% to 90%, better still from 30% to 80% andeven better still from 50% to 70% by weight of the polymer. Preferably,the proportion of the block with a Tg of less than or equal to 20° C.ranges from 5% to 75%, preferably from 15% to 50% and better still from25% to 45% by weight of the polymer.

Thus, according to a first variant, the polymer according to theinvention may comprise:

-   -   a first block with a Tg of greater than or equal to 40° C., for        example having a Tg ranging from 70 to 110° C., which is a        methyl methacrylate/acrylic acid copolymer,    -   a second block with a Tg of less than or equal to 20° C., for        example ranging from 0 to 20° C., which is a methyl acrylate        homopolymer, and    -   an intermediate block which is a methyl        methacrylate/acrylic acid/methyl acrylate copolymer.

According to a second variant, the polymer according to the inventionmay comprise:

-   -   a first block with a Tg of greater than or equal to 40° C., for        example ranging from 70 to 100° C., which is a methyl        methacrylate/acrylic acid/trifluoroethyl methacrylate copolymer,    -   a second block with a Tg of less than or equal to 20° C., for        example ranging from 0 to 20° C., which is a methyl acrylate        homopolymer, and    -   an intermediate block which is a methyl methacrylate/acrylic        acid/methyl acrylate/trifluoroethyl methacrylate random        copolymer.

According to a third variant, the polymer according to the invention maycomprise:

-   -   a first block with a Tg of greater than or equal to 40° C., for        example ranging from 85 to 115° C., which is an isobornyl        acrylate/isobutyl methacrylate copolymer,    -   a second block with a Tg of less than or equal to 20° C., for        example ranging from −85 to −55° C., which is a 2-ethylhexyl        acrylate homopolymer, and    -   an intermediate block, which is an isobornyl acrylate/isobutyl        methacrylate/2-ethylhexyl acrylate random copolymer.

According to a fourth variant, the polymer according to the inventionmay comprise:

-   -   a first block with a Tg of greater than or equal to 40° C., for        example ranging from 85 to 115° C., which is an isobornyl        acrylate/methyl methacrylate copolymer,    -   a second block with a Tg of less than or equal to 20° C., for        example ranging from −85 to −55° C., which is a 2-ethylhexyl        acrylate homopolymer, and    -   an intermediate block which is an isobornyl acrylate/methyl        methacrylate/2-ethylhexyl acrylate. random copolymer.

According to a fifth variant, the polymer according to the invention maycomprise:

-   -   a first block with a Tg of greater than or equal to 40° C., for        example ranging from 95 to 125° C., which is an isobornyl        acrylate/isobornyl methacrylate copolymer,    -   a second block with a Tg of less than or equal to 20° C., for        example ranging from −85 to −55° C., which is a 2-ethylhexyl        acrylate homopolymer, and    -   an intermediate block which is an isobornyl acrylate/isobornyl        methacrylate/2-ethylhexyl acrylate random copolymer.

According to a sixth variant, the polymer according to the invention maycomprise:

-   -   a first block with a Tg of greater than or equal to 40° C., for        example ranging from 85 to 115° C., which is an isobornyl        methacrylate/isobutyl methacrylate copolymer,    -   a second block with a Tg of less than or equal to 20° C., for        example ranging from −35 to −5° C., which is an isobutyl        acrylate homopolymer, and    -   an intermediate block which is an isobornyl        methacrylate/isobutyl methacrylate/isobutyl acrylate random        copolymer.

According to a seventh variant, the polymer according to the inventionmay comprise:

-   -   a first block with a Tg of greater than or equal to 40° C., for        example ranging from 95 to 125° C., which is an isobornyl        acrylate/isobornyl methacrylate copolymer,    -   a second block with a Tg of less than or equal to 20° C., for        example ranging from −35 to −5° C., which is an isobutyl        acrylate homopolymer, and    -   an intermediate block which is an isobornyl acrylate/isobornyl        methacrylate/isobutyl acrylate random copolymer.

According to an eighth variant, the polymer according to the inventionmay comprise:

-   -   a first block with a Tg of greater than or equal to 40° C., for        example ranging from 60 to 90° C., which is an isobornyl        acrylate/isobutyl methacrylate copolymer,    -   a second block with a Tg of less than or equal to 20° C., for        example ranging from −35 to −5° C., which is an isobutyl        acrylate homopolymer, and    -   an intermediate block which is an isobornyl acrylate/isobutyl        methacrylate/isobutyl acrylate random copolymer.

The examples that follow illustrate, in a non-limiting manner, polymerscorresponding to this first embodiment.

The amounts are expressed in grams.

EXAMPLE 1 Preparation of a poly(methyl methacrylate)/acrylic acid/methylacrylate) polymer

100 g of butyl acetate are introduced into a 1 litre reactor and thetemperature is then raised so as to pass from room temperature (25° C.)to 90° C. in 1 hour. 180 g of methyl methacrylate, 30 g of acrylic acid,40 g of butyl acetate, 70 g of isopropanol and 1.8 g of2,5-bis(2-ethylhexanoylperoxy)-2,5-dimethyl-hexane (Trigonox® 141 fromAkzo Nobel) are then added, at 90° C. and over 1 hour.

The mixture is maintained at 90° C. for 1 hour.

90 g of methyl acrylate, 70 g of butyl acetate, 20 g of isopropanol and1.2 g of 2,5-bis(2-ethylhexanoylperoxy)-2,5-dimethylhexane are thenintroduced into the above mixture, still at 90° C. and over 1 hour.

The mixture is maintained at 90° C. for 3 hours and then diluted with105 g of butyl acetate and 45 g of isopropanol, and the mixture is thencooled.

A solution containing 40% polymer-active material in a butylacetate/isopropanol mixture is obtained.

A polymer comprising a poly(methyl methacrylate/acrylic acid) firstblock with a Tg of 100° C., a polymethyl acrylate second block with a Tgof 10° C. and an intermediate block which is a methylmethacrylate/acrylic acid/polymethyl acrylate random polymer isobtained.

This polymer has a weight-average mass of 52 000 and a number-averagemass of 18 000, i.e. a polydispersity index I of 2.89.

SECOND EMBODIMENT

According to a second embodiment, the block polymer comprises a firstblock having a glass transition temperature (Tg) of between 20 and 40°C., in accordance with the blocks described in c) and a second blockhaving a glass transition temperature of less than or equal to 20° C.,as described above in b) or a glass transition temperature of greaterthan or equal to 40° C., as described in a) above.

Preferably, the proportion of the first block with a Tg of between 20and 40° C. ranges from 10% to 85% by weight of the polymer, better stillfrom 30% to 80% and even better still from 50% to 70%.

When the second block is a block with a Tg of greater than or equal to40° C., it is preferably present in a proportion ranging from 10% to 85%by weight, better still from 20% to 70% and even better still from 30%to 70% by weight of the polymer.

When the second block is a block with a Tg of less than or equal to 20°C., it is preferably present in a proportion ranging from 10% to 85% byweight, better still from 20% to 70% and even better still from 20% to50% by weight of the polymer.

Preferably, the first block with a Tg of between 20 and 40° C. is acopolymer derived from monomers which are such that the correspondinghomopolymer has a Tg of greater than or equal to 40° C., and frommonomers which are such that the corresponding homopolymer has a Tg ofless than or equal to 20° C.

Advantageously, the second block with a Tg of less than or equal to 20°C. or with a Tg of greater than or equal to 40° C. is a homopolymer.

Thus, according to a first variant of this second embodiment, the blockpolymer may comprise:

-   -   a first block with a Tg of between 20 and 40° C., for example        with a Tg of 25 to 39° C., which is a copolymer comprising at        least one methyl acrylate monomer, at least one methyl        methacrylate monomer and at least one acrylic acid monomer,    -   a second block with a Tg of greater than or equal to 40° C., for        example ranging from 85 to 125° C., which is a homopolymer        composed of methyl methacrylate monomers, and    -   an intermediate block comprising at least one methyl acrylate,        methyl methacrylate monomer, and    -   an intermediate block comprising methyl methacrylate, at least        one acrylic acid monomer and at least one methyl acrylate        monomer.

According to a second variant of this second embodiment, the blockpolymer may comprise:

-   -   a first block with a Tg of between 20 and 40° C., for example        with a Tg of 21 to 39° C., which is a copolymer comprising        isobornyl acrylate/isobutyl methacrylate/2-ethylhexyl acrylate,    -   a second block with a Tg of less than or equal to 20° C., for        example ranging from −65 to −35° C., which is a methyl        methacrylate homopolymer, and    -   an intermediate block which is an isobornyl acrylate/isobutyl        methacrylate/2-ethylhexyl acrylate random copolymer.

According to a third variant of this second embodiment, the blockpolymer may comprise:

-   -   a first block with a Tg of between 20 and 40° C., for example        with a Tg from 21 to 39° C., which is an isobornyl        acrylate/methyl acrylate/acrylic acid copolymer,    -   a second block with a Tg of greater than or equal to 40° C., for        example ranging from 85 to 115° C., which is an isobornyl        acrylate homopolymer, and    -   an intermediate block which is an isobornyl acrylate/methyl        acrylate/acrylic acid random copolymer.

By way of non-limiting illustration, the polymers corresponding to thissecond embodiment may be produced as follows.

EXAMPLE 2 Preparation of a poly(methyl methacrylate)/methylacrylate/acrylic acid) polymer

100 g of butyl acetate are introduced into a 1 litre reactor and thetemperature is then raised so as to pass from room temperature (25° C.)to 90° C. in 1 hour. 50.4 g of methyl methacrylate, 21 g of acrylicacid, 138.6 g of methyl acrylate, 40 g of butyl acetate, 70 g ofisopropanol and 1.8 g of2,5-bis(2-ethylhexanoylperoxy)-2,5-dimethylhexane (Trigonox® 141 fromAkzo Nobel) are then added, at 90° C. and over 1 hour.

The mixture is maintained at 90° C. for 1 hour.

90 g of methyl methacrylate, 70 g of butyl acetate, 20 g of isopropanoland 1.2 g of 2,5-bis(2-ethylhexanoylperoxy)-2,5-dimethylhexane are thenintroduced into the above mixture, still at 90° C. and over 1 hour.

The mixture is maintained at 90° C. for 3 hours and then diluted with105 g of butyl acetate and 45 g of isopropanol, and the mixture is thencooled.

A solution containing 40% polymer active material in a butylacetate/isopropanol mixture is obtained.

The polymer obtained comprises a first poly(methyl acrylate/methylmethacrylate/acrylic acid) block with a Tg of 35° C., a secondpoly(methyl methacrylate) block with a Tg of 100° C. and an intermediateblock that is a methyl methacrylate/acrylic acid/polymethyl acrylaterandom polymer.

Generally, the compositions of the invention contain from 0.1% to 60% byweight, preferably from 0.5% to 50% by weight and more preferably from1% to 40% by weight of the block polymer according to the invention.

Solvent Medium

The cosmetic composition may comprise an organic solvent medium or amixture of organic solvents.

The organic solvent may be chosen from:

-   -   ketones that are liquid at room temperature, such as methyl        ethyl ketone, methyl isobutyl ketone, diisobutyl ketone,        isophorone, cyclohexanone or acetone;    -   alcohols that are liquid at room temperature, such as ethanol,        isopropanol, diacetone alcohol, 2-butoxy-ethanol or        cyclohexanol;    -   glycols that are liquid at room temperature, such as ethylene        glycol, propylene glycol, pentylene glycol or glycerol;    -   propylene glycol ethers that are liquid at room temperature such        as propylene glycol monomethyl ether, propylene glycol        monomethyl ether acetate or dipropylene glycol mono-n-butyl        ether; cyclic ethers such as γ-butyrolactone;    -   short-chain esters (containing from 3 to 8 carbon atoms in        total) such as ethyl acetate, methyl acetate, propyl acetate,        isopropyl acetate, n-butyl acetate, isopentyl acetate,        methoxypropyl acetate or butyl lactate;    -   ethers that are liquid at room temperature, such as diethyl        ether, dimethyl ether or dichlorodiethyl ether;    -   alkanes that are liquid at room temperature, such as decane,        heptane, dodecane or cyclohexane; alkyl sulphoxides, such as        dimethyl sulphoxide; aldehydes that are liquid at room        temperature, such as benzaldehyde or acetaldehyde; heterocyclic        compounds such as tetrahydrofuran; propylene carbonate or ethyl        3-ethoxypropionate;    -   mixtures thereof.

The organic solvent medium preferably has a polarity P ranging from0.422 to 0.725.

The polarity is defined as a function of the solubility parametersaccording to the Hansen solubility space, according to the followingrelationship:P=√(δp ² +δh ²)/δt

-   -   δh characterizing the specific forces of interaction (such as        hydrogen bonding, acid/base bonding, donor/acceptor bonding,        etc.);    -   δp characterizing the Debye interaction forces between permanent        dipoles and also the Keesom interaction forces between induced        dipoles and permanent dipoles; and    -   δt=√(δp²+δh²+δd²), δd characterizing the London dispersion        forces derived from the formation of induced dipoles during        molecular impacts.

The definition and calculation of the solubility parameters in theHansen three-dimensional solubility space are described in the articleby C. M. Hansen: “The three dimensional solubility parameters” J. PaintTechnol. 39, 105 (1967).

When the solvent medium comprises a mixture of solvents, the polarity isdetermined from the solubility parameters of the mixture, which arethemselves determined from those of the compounds taken separately,according to the following relationships:${{\delta\quad{dmixt}} = {\sum\limits_{i}{{xi}\quad\delta\quad{di}}}};{{\delta\quad{pmixt}} = {{\sum\limits_{i}{{xi}\quad\delta\quad{pl}\quad{and}\quad\delta\quad{hmixt}}} = {\sum\limits_{i}{{xi}\quad\delta\quad{hi}}}}}$in which xi represents the volume fraction of the compound i in themixture.

As organic solvents with a polarity ranging from 0.422 to 0.725, mentionmay be made in particular of methyl acetate, isopropyl acetate,methoxypropyl acetate, butyl lactate, acetone, methyl ethyl ketone,diacetone alcohol, γ-butyrolactone, tetrahydrofuran, propylenecarbonate, ethyl 3-ethoxypropionate and dimethyl sulphoxide, andmixtures thereof.

The organic solvent medium may represent from 10% to 95% by weight,preferably from 15% to 80% by weight and better still from 20% to 60% byweight, relative to the total weight of the composition.

Additional Film-forming Polymer

The composition may comprise, besides the block polymer of thecomposition according to the invention, an additional polymer such as afilm-forming polymer.

Among the film-forming polymers that may be used in the composition ofthe present invention, mention may be made of synthetic polymers, offree-radical type or of polycondensate type, and polymers of naturalorigin, and mixtures thereof.

The film-forming polymer may be chosen in particular fromcellulose-based polymers such as cellulose acetate, celluloseacetobutyrate, cellulose acetopropionate or ethylcellulose, oralternatively polyurethanes, acrylic polymers, vinyl polymers,polyvinylbutyrals, alkyd resins, resins derived from aldehydecondensation products such as arylsulphonamide-formaldehyde resins, forinstance toluenesulphonamide-formaldehyde resin, andarylsulphonamide-epoxy resins.

Film-forming polymers that may especially be used include thetoluenesulphonamide-formaldehyde resins “Ketjentflex MS80” from thecompany Akzo or “Santolite MHP” or “Santolite MS 80” from the companyFaconnier or “Resimpol 80” from the company Pan Americana, the alkydresin “Beckosol ODE 230-70-E” from the company Dainippon, the acrylicresin “Acryloid B66” from the company Rohm & Haas, and the polyurethaneresin “Trixene PR 4127” from the company Baxenden.

The additional film-forming polymer may be present in the compositionaccording to the invention in a content ranging from 0.1% to 60% byweight, preferably ranging from 2% to 40% by weight and better stillfrom 5% to 25% by weight, relative to the total weight of thecomposition.

Plasticizer

The composition may also comprise at least one plasticizer. Inparticular, mention may be made, alone or as a mixture, of the usualplasticizers, such as:

-   -   glycols and derivatives thereof such as diethylene glycol ethyl        ether, diethylene glycol methyl ether, diethylene glycol butyl        ether or diethylene glycol hexyl ether, ethylene glycol ethyl        ether, ethylene glycol butyl ether or ethylene glycol hexyl        ether;    -   glycerol esters,    -   propylene glycol derivatives and in particular propylene glycol        phenyl ether, propylene glycol diacetate, dipropylene glycol        butyl ether, tripropylene glycol butyl ether, propylene glycol        methyl ether, dipropylene glycol ethyl ether, tripropylene        glycol methyl ether, diethylene glycol methyl ether and        propylene glycol butyl ether,    -   acid esters, especially carboxylic acid esters, such as        citrates, phthalates, adipates, carbonates, tartrates,        phosphates or sebacates,    -   oxyethylenated derivatives such as oxyethylenated oils,        especially plant oils such as castor oil;        mixtures thereof.

The amount of plasticizer may be chosen by a person skilled in the arton the basis of his general knowledge, so as to obtain a compositionwith cosmetically acceptable properties. The plasticizer is preferablypresent in an amount of less than 20%, preferably less than 15%, betterstill less than 10% and even better still less than 5% by weight,relative to the total weight of the composition. The compositionaccording to the invention is preferably free of plasticizer.

Dyestuff

The composition according to the invention may also comprise one or moredyestuffs chosen from water-soluble dyes and pulverulent dyestuffs, forinstance pigments, nacres and flakes that are well known to thoseskilled in the art. The dyestuffs may be present in the composition in acontent ranging from 0.01% to 50% by weight and preferably from 0.01% to30% by weight, relative to the weight of the composition.

The term “pigments” should be understood as meaning white or coloured,mineral or organic particles of any shape, which are insoluble in thephysiological medium and which are intended to colour the composition.

The term “nacres” should be understood as meaning iridescent particlesof any shape, produced especially by certain molluscs in their shell, oralternatively synthesized.

The pigments may be white or coloured, and mineral and/or organic. Amongthe mineral pigments that may be mentioned are titanium dioxide,optionally surface-treated, zirconium oxide or cerium oxide, and alsozinc oxide, iron oxide (black, yellow or red) or chromium oxide,manganese violet, ultramarine blue, chromium hydrate and ferric blue,and metal powders, for instance aluminium powder or copper powder. Amongthe organic pigments that may be mentioned are carbon black, pigments ofD & C type, and lakes based on cochineal carmine or on barium,strontium, calcium or aluminium.

The nacreous pigments may be chosen from white nacreous pigments such asmica coated with titanium or with bismuth oxychloride, coloured nacreouspigments such as titanium mica coated with iron oxides, titanium micacoated especially with ferric blue or chromium oxide, titanium micacoated with an organic pigment of the abovementioned type and alsonacreous pigments based on bismuth oxychloride.

The water-soluble dyes are, for example, beetroot juice or methyleneblue.

The composition according to the invention may also comprise one or morefillers, especially in a content ranging from 0.01% to 50% by weight andpreferably ranging from 0.01% to 30% by weight, relative to the totalweight of the composition. The term “fillers” should be understood asmeaning colourless or white, mineral or synthetic particles of anyshape, which are insoluble in the medium of the composition,irrespective of the temperature at which the composition ismanufactured. These fillers serve especially to modify the rheology orthe texture of the composition.

The fillers may be mineral or organic in any form, platelet-shaped,spherical or oblong, irrespective of the crystallographic form (forexample leaflet, cubic, hexagonal, orthorhombic, etc.). Mention may bemade of talc, mica, silica, kaolin, polyamide (Nylon®) powders (Orgasol®from Atochem), poly-β-alanine powder and polyethylene powder, powders ofpolytetrafluoroethylene polymers (Teflon®), lauroyllysine, starch, boronnitride, hollow polymer microspheres such as those of polyvinylidenechloride/acrylonitrile, for instance Exapancel® (Nobel Industrie) oracrylic acid copolymers (Polytrap® from the company Dow Corning) andsilicone resin microbeads (for example Tospearls® from Toshiba),elastomeric polyorganosiloxane particles, precipitated calciumcarbonate, magnesium carbonate, magnesium hydrocarbonate,hydroxyapatite, hollow silica microspheres (Silica Beads® fromMaprecos), glass or ceramic microcapsules, and metal soaps derived fromorganic carboxylic acids containing from 8 to 22 carbon atoms andpreferably from 12 to 18 carbon atoms, for example zinc, magnesium orlithium stearate, zinc laurate or magnesium myristate.

Other Additives

The composition may also comprise other ingredients commonly used incosmetic compositions. Such ingredients may be chosen from spreadingagents, wetting agents, dispersants, antifoams, preserving agents,UV-screening agents, active agents, surfactants, moisturizers,fragrances, neutralizers, stabilizers and antioxidants.

Needless to say, a person skilled in the art will take care to selectthis or these optional additional compound(s), and/or the amountthereof, such that the advantageous properties of the compositionaccording to the invention are not, or are not substantially, adverselyaffected by the envisaged addition.

Needless to say, a person skilled in the art will take care to selectthis or these optional additional compound(s) and/or the amount thereof,such that the advantageous properties of the composition for the useaccording to the invention are not, or are not substantially, adverselyaffected by the envisaged addition.

A subject of the present invention is also a cosmetic assemblycomprising:

-   -   a container delimiting at least one compartment, the said        container being closed by a closing member; and    -   a composition placed inside the said compartment, the        composition being in accordance with the invention.

The container may be in any adequate form. It may especially be in theform of a bottle, a case or a tube.

The closing member may be in the form of a removable stopper.

The container is preferably equipped with an applicator to allow theapplication of the product to the nails. Such an applicator may be inthe form of a fine brush consisting of at least one tuft of hairs. Thetuft of hairs may be embedded at the end of a rod borne by the closingmember. The hairs are preferably oriented along the axis of the rod. Thehairs may be embedded by means of stapling, bonded, or obtained bymoulding.

Alternatively, the applicator is in the form of a tape made of porousmaterial, especially of open-cell foam or of felt.

Alternatively also, the applicator may be in the form of a spatula,especially made of elastomeric material.

The closing member may be coupled to the container by screwing.Alternatively, the coupling between the closing member and the containeris done other than by screwing, especially via a bayonet mechanism or byclick-fastening. The term “click-fastening” in particular means anysystem involving the crossing of a bead or cord of material by elasticdeformation of a portion, especially of the closing member, followed byreturn to the elastically unconstrained position of the said portionafter the crossing of the bead or cord.

The container is preferably made of glass. However, materials other thanglass may be used. Examples that will be mentioned include certainthermoplastic materials appropriately chosen so as to be compatible withthe composition. Alternatively also, the container may be made of metal.

The examples that follow illustrate the invention in a non-limitingmanner.

EXAMPLE 3 Nail Varnish

Polymer of Example 1 23.8 g AM Butyl acetate 24.99 g Isopropanol 10.71 gHexylene glycol 2.5 g DC Red 7 Lake 1 g Hectorite modified withstearyldimethyl- 1.3 g benzylammonium chloride (Bentone ® 27V fromElementis)

EXAMPLE 4 Nail Varnish

Polymer of Example 2 23.8 g AM Butyl acetate 24.99 g Isopropanol 10.71 gHexylene glycol 2.5 g DC Red 7 Lake 1 g Hectorite modified with 1.3 gstearyldimethylbenzylammonium chloride (Bentone ® 27V from Elementis)Ethyl acetate qs 100 g

1. Nitrocellulose-free nail varnish composition, characterized in that it comprises, in a cosmetically acceptable organic solvent medium, at least one film-forming linear ethylenic block polymer, the said block polymer being such that, when it is present in sufficient amount in the composition, the mean gloss at 20° of a deposit of the said composition, once spread onto a support, is greater than or equal to 50 out of
 100. 2. Composition according to claim 1, characterized in that the block polymer is non-elastomeric.
 3. Composition according to claim 1 or 2, characterized in that the block polymer is free of styrene units.
 4. Composition according to one of the preceding claims, characterized in that the block polymer is an ethylenic polymer derived from aliphatic ethylenic monomers comprising a carbon-carbon double bond and at least one ester group —COO— or amide —CON— group.
 5. Composition according to one of the preceding claims, characterized in that the block polymer is not soluble at an active material content of at least 1% by weight in water or in a mixture of water and of linear or branched lower monoalcohols containing from 2 to 5 carbon atoms, without pH modification, at room temperature (25° C.).
 6. Composition according to one of the preceding claims, characterized in that the block polymer contains first and second blocks that are linked together via an intermediate segment comprising at least one constituent monomer of the first block and at least one constituent monomer of the second block.
 7. Composition according to one of the preceding claims, characterized in that the block polymer contains first and second blocks that have different glass transition temperatures (Tg).
 8. Composition according to the preceding claim, characterized in that the first and second blocks are linked together via an intermediate segment with a glass transition temperature between the glass transition temperatures of the first and second blocks.
 9. Composition according to any one of the preceding claims, characterized in that the block polymer contains first and second blocks that are incompatible in the said organic liquid medium.
 10. Composition according to one of the preceding claims, characterized in that the block polymer has a polydispersity index I of greater than
 2. 11. Composition according to claim 7, characterized in that the first block of the polymer is chosen from: a) a block with a Tg of greater than or equal to 40° C., b) a block with a Tg of less than or equal to 20° C., c) a block with a Tg of between 20 and 40° C., and the second block is chosen from a category a), b) or c) that is different from the first block.
 12. Composition according to claim 11, characterized in that the block with a Tg of greater than or equal to 40° C. is totally or partially derived from one or more monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of greater than or equal to 40° C.
 13. Composition according to the preceding claim, characterized in that the monomers whose corresponding homopolymer has a glass transition temperature of greater than or equal to 40° C. are chosen from the following monomers: methacrylates of formula CH₂═C(CH₃)—COOR₁ in which R₁ represents a linear or branched unsubstituted alkyl group containing from 1 to 4 carbon atoms, such as a methyl, ethyl, propyl or isobutyl group or R₁ represents a C₄ to C₁₂ cycloalkyl group, acrylates of formula CH₂═CH—COOR₂ in which R₂ represents a C₄ to C₁₂ cycloalkyl group such as isobornyl acrylate or a tert-butyl group, (meth)acrylamides of formula:

in which R₇ and R₈, which may be identical or different, each represent a hydrogen atom or a linear or branched alkyl group with 1 to 12 carbon atoms such as an n-butyl, t-butyl, isopropyl, isohexyl, isooctyl or isononyl group; or R₇ represents H and R₈ represents a 1,1-dimethyl-3-oxobutyl group, and R′ denotes H or methyl, and mixtures thereof.
 14. Composition according to claim 12 or 13, characterized in that the monomers whose corresponding homopolymer has a glass transition temperature of greater than or equal to 40° C. are chosen from methyl methacrylate, isobutyl (meth)acrylate and isobornyl (meth)acrylate, and mixtures thereof.
 15. Composition according to claim 11, characterized in that the block with a Tg of less than or equal to 20° C. is totally or partially derived from one or more monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of less than or equal to 20° C.
 16. Composition according to claim 15, characterized in that the monomers whose corresponding homopolymer has a glass transition temperature of less than or equal to 20° C. are chosen from the following monomers: acrylates of formula CH₂═CHCOOR₃, R₃ representing a linear or branched C₁ to C₁₂ unsubstituted alkyl group, with the exception of the tert-butyl group, in which one or more hetero atoms chosen from O, N and S is (are) optionally intercalated; methacrylates of formula CH₂═C(CH₃)—COOR₄, R₄ representing a linear or branched C₆ to C₁₂ unsubstituted alkyl group, in which one or more hetero atoms chosen from O, N and S is (are) optionally intercalated; vinyl esters of formula R₅—CO—O—CH═CH₂ in which R₅ represents a linear or branched C₄ to C₁₂ alkyl group; C₄ to C₁₂ alkyl vinyl ethers, N-(C₄ to C₁₂)alkyl acrylamides, such as N-octylacrylamide; and mixtures thereof.
 17. Composition according to claim 15 or 16, characterized in that the monomers whose corresponding homopolymer has a glass transition temperature of less than or equal to 20° C. are chosen from alkyl acrylates whose alkyl chain contains from 1 to 10 carbon atoms, with the exception of the tert-butyl group.
 18. Composition according to claim 11, characterized in that the block with a Tg of between 20 and 40° C. is totally or partially derived from one or more monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of between 20 and 40° C.
 19. Composition according to claim 11, characterized in that the block with a Tg of between 20 and 40° C. is totally or partially derived from monomers which are such that the corresponding homopolymer has a Tg of greater than or equal to 40° C. and from monomers which are such that the corresponding homopolymer has a Tg of less than or equal to 20° C.
 20. Composition according to claim 18 or 19, characterized in that the block with a Tg of between 20 and 40° C. is totally or partially derived from monomers chosen from methyl methacrylate, isobornyl acrylate, isobornyl methacrylate, butyl acrylate and 2-ethylhexyl acrylate, and mixtures thereof.
 21. Composition according to one of claims 11 to 20, characterized in that it comprises a block polymer comprising at least a first block and at least a second block, the first block having a glass transition temperature (Tg) of greater than or equal to 40° C., and the second block having a glass transition temperature of less than or equal to 20° C.
 22. Composition according to the preceding claim, characterized in that the first block is totally or partially derived from one or more monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of greater than or equal to 40° C.
 23. Composition according to claim 22, characterized in that the first block is a copolymer derived from monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of greater than or equal to 40° C.
 24. Composition according to claim 22 or 23, characterized in that the monomers whose corresponding homopolymer has a glass transition temperature of greater than or equal to 40° C. are chosen from the following monomers: methacrylates of formula CH₂═C(CH₃)—COOR₁ in which R₁ represents a linear or branched unsubstituted alkyl group containing from 1 to 4 carbon atoms, such as a methyl, ethyl, propyl or isobutyl group or R₁ represents a C₄ to C₁₂ cycloalkyl group, acrylates of formula CH₂═CH—COOR₂ in which R₂ represents a C₄ to C₁₂ cycloalkyl group such as isobornyl acrylate or a tert-butyl group, (meth)acrylamides of formula:

in which R₇ and R₈, which may be identical or different, each represent a hydrogen atom or a linear or branched alkyl group with 1 to 12 carbon atoms such as an n-butyl, t-butyl, isopropyl, isohexyl, isooctyl or isononyl group; or R₇ represents H and R₈ represents a 1,1-dimethyl-3-oxobutyl group, and R′ denotes H or methyl, and mixtures thereof.
 25. Composition according to one of claims 22 to 24, characterized in that the monomers whose corresponding homopolymer has a glass transition temperature of greater than or equal to 40° C. are chosen from methyl methacrylate, isobutyl methacrylate and isobornyl (meth)acrylate, and mixtures thereof.
 26. Composition according to one of claims 22 to 25, characterized in that the proportion of the first block ranges from 20% to 90%, better still from 30% to 80% and even better still from 50% to 70%, by weight of the polymer.
 27. Composition according to one of claims 21 to 26, characterized in that the second block is totally or partially derived from one or more monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of less than or equal to 20° C.
 28. Composition according to one of claims 21 to 27, characterized in that the second block is a homopolymer derived from monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of less than or equal to 20° C.
 29. Composition according to one of claims 27 or 28, characterized in that the monomers whose corresponding homopolymer has a glass transition temperature of less than or equal to 20° C. are chosen from the following monomers: acrylates of formula CH₂═CHCOOR₃, R₃ representing a linear or branched C₁ to C₁₂ unsubstituted alkyl group, with the exception of the tert-butyl group, in which one or more hetero atoms chosen from O, N and S is (are) optionally intercalated; methacrylates of formula CH₂═C(CH₃)—COOR₄, R₄ representing a linear or branched C₆ to C₁₂ unsubstituted alkyl group, in which one or more hetero atoms chosen from O, N and S is (are) optionally intercalated; vinyl esters of formula R₅—CO—O—CH═CH₂ in which R₅ represents a linear or branched C₄ to C₁₂ alkyl group; C₄ to C₁₂ alkyl vinyl ethers, N-(C₄ to C₁₂)alkyl acrylamides, such as N-octylacrylamide; and mixtures thereof.
 30. Composition according to one of claims 27 to 29, characterized in that the monomers whose corresponding homopolymer has a glass transition temperature of less than or equal to 20° C. are chosen from alkyl acrylates whose alkyl chain contains from 1 to 10 carbon atoms, with the exception of the tert-butyl group.
 31. Composition according to one of claims 21 to 30, characterized in that the proportion of the second block with a Tg of less than or equal to 20° C. ranges from 5% to 75%, better still from 15% to 50% and even better still from 25% to 45%, by weight of the polymer.
 32. Composition according to one of claims 11 to 20, characterized in that it comprises a block polymer comprising at least a first block and at least a second block, the first block having a glass transition temperature (Tg) of between 20 and 40° C. and the second block having a glass transition temperature of less than or equal to 20° C. or a glass transition temperature of greater than or equal to 40° C.
 33. Composition according to the preceding claim, characterized in that the first block with a Tg of between 20 and 40° C. is totally or partially derived from one or more monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of between 20 and 40° C.
 34. Composition according to claim 32 or 33, characterized in that the first block with a Tg of between 20 and 40° C. is a copolymer derived from monomers which are such that the corresponding homopolymer has a Tg of greater than or equal to 40° C., and from monomers which are such that the corresponding homopolymer has a Tg of less than or equal to 20° C.
 35. Composition according to one of claims 32 to 34, characterized in that the first block with a Tg of between 20 and 40° C. is derived from monomers chosen from methyl methacrylate, isobornyl acrylate, isobornyl methacrylate, butyl acrylate and 2-ethylhexyl acrylate, and mixtures thereof.
 36. Composition according to one of claims 32 to 35, characterized in that the proportion of the first block with a Tg of between 20 and 40° C. ranges from 10% to 85%, better still from 30% to 80% and even better still from 50% to 70% by weight of the polymer.
 37. Composition according to any one of claims 32 to 35, characterized in that the second block has a Tg of greater than or equal to 40° C. and is totally or partially derived from one or more monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of greater than or equal to 40° C.
 38. Composition according to any one of claims 32 to 37, characterized in that the second block has a Tg of greater than or equal to 40° C. and is a homopolymer derived from monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of greater than or equal to 40° C.
 39. Composition according to either of claims 37 and 38, characterized in that the monomers whose corresponding polymer has a glass transition temperature of greater than or equal to 40° C. are chosen from the following monomers: methacrylates of formula CH₂═C(CH₃)—COOR₁ in which R₁ represents a linear or branched unsubstituted alkyl group containing from 1 to 4 carbon atoms, such as a methyl, ethyl, propyl or isobutyl group or R₁ represents a C₄ to C₁₂ cycloalkyl group, acrylates of formula CH₂═CH—COOR₂ in which R₂ represents a C₄ to C₁₂ cycloalkyl group such as isobornyl acrylate or a tert-butyl group, (meth)acrylamides of formula:

in which R₇ and R₈, which may be identical or different, each represent a hydrogen atom or a linear or branched alkyl group with 1 to 12 carbon atoms such as an n-butyl, t-butyl, isopropyl, isohexyl, isooctyl or isononyl group; or R₇ represents H and R₈ represents a 1,1-dimethyl-3-oxobutyl group, and R′ denotes H or methyl, and mixtures thereof.
 40. Composition according to one of claims 36 to 39, characterized in that the monomers whose corresponding homopolymer has a glass transition temperature of greater than or equal to 40° C. are chosen from methyl methacrylate, isobutyl methacrylate and isobornyl (meth)acrylate, and mixtures thereof.
 41. Composition according to one of claims 37 to 40, characterized in that the proportion of the second block with a Tg of greater than or equal to 40° C. ranges from 10% to 85%, preferably from 20% to 70% and better still from 30% to 70%, by weight of the polymer.
 42. Composition according to one of claims 32 to 41, characterized in that the second block has a Tg of less than or equal to 20° C. and is totally or partially derived from one or more monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of less than or equal to 20° C.
 43. Composition according to one of claims 32 to 41, characterized in that the second block has a Tg of less than or equal to 20° C. and is a homopolymer derived from monomers which are such that the homopolymer prepared from these monomers has a glass transition temperature of less than or equal to 20° C.
 44. Composition according to claim 42 or 43, characterized in that the monomers whose corresponding homopolymer has a glass transition temperature of less than or equal to 20° C. are chosen from the following monomers: acrylates of formula CH₂═CHCOOR₃, R₃ representing a linear or branched C₁ to C₁₂ unsubstituted alkyl group, with the exception of the tert-butyl group, in which one or more hetero atoms chosen from O, N and S is (are) optionally intercalated; methacrylates of formula CH₂═C(CH₃)—COOR₄, R₄ representing a linear or branched C₆ to C₁₂ unsubstituted alkyl group, in which one or more hetero atoms chosen from O, N and S is (are) optionally intercalated; vinyl esters of formula R₅—CO—O—CH═CH₂ in which R₅ represents a linear or branched C₄ to C₁₂ alkyl group; C₄ to C₁₂ alkyl vinyl ethers, N-(C₄ to C₁₂)alkyl acrylamides, such as N-octylacrylamide; and mixtures thereof.
 45. Composition according to one of claims 42 to 44, characterized in that the monomers whose homopolymers have glass transition temperatures of less than or equal to 20° C. are chosen from alkyl acrylates whose alkyl chain contains from 1 to 10 carbon atoms, with the exception of the tert-butyl group.
 46. Composition according to one of claims 42 to 45, characterized in that the proportion of the block with a glass transition temperature of greater than or equal to 40° C. ranges from 20% to 90%, better still from 30% to 80% and even better still from 50% to 70%, by weight of the polymer.
 47. Composition according to one of claims 5 to 8 or any one of their preceding dependant claims, characterized in that the first block and/or the second block comprises at least one additional monomer.
 48. Composition according to the preceding claim, characterized in that the additional monomer is chosen from hydrophilic monomers and ethylenically unsaturated monomers comprising one or more silicon atoms, and mixtures thereof.
 49. Composition according to claim 47 or 48, characterized in that the additional monomer is chosen from: a) hydrophilic monomers such as: ethylenically unsaturated monomers comprising at least one carboxylic or sulfonic acid function, for instance: acrylic acid, methacrylic acid, crotonic acid, maleic anhydride, itaconic acid, fumaric acid, maleic acid, acrylamidopropanesulfonic acid, vinylbenzoic acid, vinylphosphoric acid, and salts thereof, ethylenically unsaturated monomers comprising at least one tertiary amine function, for instance 2-vinylpyridine, 4-vinylpyridine, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate and dimethylaminopropylmethacrylamide, and salts thereof, methacrylates of formula CH₂═C(CH₃)—COOR₆ in which R₆ represents a linear or branched alkyl group containing from 1 to 4 carbon atoms, such as a methyl, ethyl, propyl or isobutyl group, the said alkyl group being substituted with one or more substituents chosen from hydroxyl groups (for instance 2-hydroxypropyl methacrylate and 2-hydroxyethyl methacrylate) and halogen atoms (Cl, Br, I or F), such as trifluoroethyl methacrylate, methacrylates of formula CH₂═C(CH₃)—COOR₉, R₉ representing a linear or branched C₆ to C₁₂ alkyl group in which one or more hetero atoms chosen from O, N and S is (are) optionally intercalated, the said alkyl group being substituted with one or more substituents chosen from hydroxyl groups and halogen atoms (Cl, Br, I or F); acrylates of formula CH₂═CHCOOR₁₀, R₁₀ representing a linear or branched C₁ to C₁₂ alkyl group substituted with one or more substituents chosen from hydroxyl groups and halogen atoms (Cl, Br, I or F), such as 2-hydroxypropyl acrylate and 2-hydroxyethyl acrylate, or R₁₀ represents a (C₁ to C₁₂) alkyl-O-POE (polyoxyethylene) with repetition of the oxyethylene unit 5 to 30 times, for example methoxy-POE, or R₁₀ represents a polyoxyethylenated group comprising from 5 to 30 ethylene oxide units, and b) ethylenically unsaturated monomers comprising one or more silicon atoms, such as methacryloxypropyltrimethoxysilane and methacryloxypropyltris(trimethylsiloxy)silane, and mixtures thereof.
 50. Composition according to either of claims 47 and 48, characterized in that each of the first and second blocks comprises at least one additional monomer chosen from acrylic acid, (meth)acrylic acid and trifluoroethyl methacrylate, and mixtures thereof.
 51. Composition according to either of claims 47 and 48, characterized in that each of the first and second blocks comprises at least one monomer chosen from (meth)acrylic acid esters and optionally at least one additional monomer such as (meth)acrylic acid, and mixtures thereof.
 52. Composition according to either of claims 47 and 48, characterized in that each of the first and second blocks is totally derived from at least one monomer chosen from (meth)acrylic acid esters and optionally from at least one additional monomer such as (meth)acrylic acid, and mixtures thereof.
 53. Composition according to one of claims 47 to 52, characterized in that the additional monomer(s) represent(s) from 1% to 30% by weight relative to the total weight of the first and/or second blocks.
 54. Composition according to claim 7 or any one of its preceding dependant claims, characterized in that the difference between the glass transition temperatures (Tg) of the first and second blocks is greater than 10° C., better still greater than 20° C., preferably greater than 30° C. and better still greater than 40° C.
 55. Composition according to claim 10, characterized in that the block polymer has a polydispersity index of greater than or equal to 2.5 and preferably greater than or equal to 2.8.
 56. Composition according to claim 55, characterized in that has a polydispersity index of between 2.8 and
 6. 57. Composition according to one of the preceding claims, characterized in that the block polymer has a weight-average mass (Mw) which is less than or equal to 300
 000. 58. Composition according to claim 57, characterized in that the weight-average mass (Mw) ranges from 35 000 to 200 000 and better still from 45 000 to 150
 000. 59. Composition according to claim 58, characterized in that the wight-average mass (Mn) is less than or equal to 70
 000. 60. Composition according to one of claims 57 to 59, whose weight-average mass (Mn) ranges from 10 000 to 60 000 and better still from 12 000 to 50
 000. 61. Composition according to any one of the preceding claims, characterized in that it comprises from 0.1% to 60% by weight of polymer active material, preferably from 5% to 50% by weight and more preferably from 10% to 40% by weight.
 62. Composition according to one of the preceding claims, characterized in that the organic solvent medium comprises an organic solvent chosen from: ketones that are liquid at room temperature, such as methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, isophorone, cyclohexanone or acetone; alcohols that are liquid at room temperature, such as ethanol, isopropanol, diacetone alcohol, 2-butoxy-ethanol or cyclohexanol; glycols that are liquid at room temperature, such as ethylene glycol, propylene glycol, pentylene glycol or glycerol; propylene glycol ethers that are liquid at room temperature such as propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate or dipropylene glycol mono-n-butyl ether; cyclic ethers such as γ-butyrolactone; short-chain esters (containing from 3 to 8 carbon atoms in total) such as ethyl acetate, methyl acetate, propyl acetate, isopropyl acetate, n-butyl acetate, isopentyl acetate, methoxypropyl acetate or butyl lactate; ethers that are liquid at room temperature, such as diethyl ether, dimethyl ether or dichlorodiethyl ether; alkanes that are liquid at room temperature, such as decane, heptane, dodecane or cyclohexane; alkyl sulphoxides, such as dimethyl sulphoxide; aldehydes that are liquid at room temperature, such as benzaldehyde or acetaldehyde; heterocyclic compounds such as tetrahydrofuran; propylene carbonate or ethyl 3-ethoxypropionate; mixtures thereof.
 63. Composition according to claim 62, characterized in that the organic solvent medium has a polarity P ranging from 0.422 to 0.725.
 64. Composition according to claim 62 or 63, characterized in that the organic solvent medium represents from 10% to 95% by weight, preferably from 15% to 80% by weight and better still from 20% to 60% by weight, relative to the total weight of the composition.
 65. Composition according to any one of the preceding claims, characterized in that it comprises a dyestuff.
 66. Composition according to the preceding claim, characterized in that the dyestuff is present in a content ranging from 0.01% to 50% by weight and preferably from 0.01% to 30% by weight, relative to the total weight of the composition.
 67. Composition according to the preceding claim, characterized in that it contains a plasticizer, which is present in an amount of less than 20%, preferably less than 15%, better still less than 10% and even better still less than 5% by weight, relative to the total weight of the composition.
 68. Composition according to the preceding claim, characterized in that the mean gloss of the composition measured at 20° is greater than or equal to 50 out of 100, better still greater than or equal to 55, even better still greater than or equal to 60, even better still greater than or equal to 65, even better still greater than or equal to 70 or even better still greater than or equal to 75 out of 100, or even greater than or equal to 80 out of
 100. 69. Composition according to the preceding claim, characterized in that the mean gloss of the composition, once spread onto a support, measured at 60° is greater than or equal to 50, better still greater than or equal to 60, better still greater than or equal to 65, better still greater than or equal to 70, better still greater than or equal to 75, better still greater than or equal to 80, better still greater than or equal to 85 or better still greater than or equal to 90 out of
 100. 70. Cosmetic assembly comprising: a) a container delimiting at least one compartment, the said container being closed by a closing member; and b) a composition placed inside the said compartment, the composition being in accordance with any one of the preceding claims.
 71. Cosmetic assembly according to claim 70, characterized in that the container is at least partly made of glass.
 72. Cosmetic assembly according to claim 70, characterized in that the container is at least partly made of at least one material other than glass.
 73. Assembly according to any one of claims 70 to 72, characterized in that, in the closed position of the container, the closing member is screwed onto the container.
 74. Assembly according to any one of claims 70 to 72, characterized in that, in the closed position of the container, the closing member is coupled to the container other than by screwing, especially by click-fastening.
 75. Assembly according to any one of claims 70 to 74, characterized in that it comprises an applicator in the form of a fine brush comprising at least one tuft of hairs.
 76. Assembly according to any one claims 70 to 74, characterized in that it comprises an applicator other than a fine brush.
 77. Non-therapeutic cosmetic makeup or care process for the nails, comprising the application to the nails of at least one coat of a nail varnish composition according to one of claims 1 to
 69. 